Fabricated panel

ABSTRACT

A self-supporting composite material is made with a shape conforming to the shape of an enclosure within which the composite material is incubated and molded. In on embodiment, a lid with at least one extrusion is placed over the enclosure to form a void in the final product corresponding to the extrusion. In another embodiment, a tool with extruded features is pressed into a face of the product in the enclosure to mold features into the finished product.

This is a Division of U.S. Ser. No. 12/001,556, filed Dec. 12, 2007.

This invention claims the benefit of Provisional Patent Application No. 60/875,243 filed Dec. 15, 2006 and Provisional Patent Application No. 60/927,458 filed May 3, 2007, the contents of each being incorporated by reference herein.

This invention relates to a feature molding. More particularly, this invention relates to a feature molding made in part of mycelium and having embedded materials.

BACKGROUND OF THE INVENTION

As described in the parent application, fungi are some of the fastest growing organisms known. They exhibit excellent bioefficiency, of up to 80%, and are adept at converting raw inputs into a range of components and compositions. Fungi are composed primarily of a cell wall that is constantly being extended at the tips of the hyphae. Unlike the cell wall of a plant, which is composed primarily of cellulose, or the structural component of an animal cell, which relies on collagen, the structural oligosaccharides of the cell wall of fungi relay primarily on chitin. Chitin is strong, hard substance, also found in the exoskeletons of arthropods. Chitin is already used within multiple industries as a purified substance. These uses include: water purification, food additives for stabilization, binders in fabrics and adhesives, surgical thread, and medicinal applications.

It is an object of this invention to provide a composite with a unique shape with internal features.

It is another object of the invention to provide a composite made in part of cultured fungi and having molded features in a surface thereof.

Briefly, the invention provides a self-supporting composite material comprising a substrate of discrete particles and a network of interconnected mycelia cells extending through and around the discrete particles and bonding the discrete particles together wherein the composite material has at least one exterior surface having at least one feature relief molded therein.

This method of making a composite uses the growth of hyphae, collectively referred to as mycelia or mycelium, to create materials composed of the fungi cellular tissue. This method expressly includes the growth of hyphae to create composites, utilizing particles, fibers, meshes, rods, elements, and other bulking agents, as an internal component of the composite, where the hyphae and other cellular tissue and extra cellular compounds act as a bonding agent and structural component.

In one embodiment, the method of making a composite material comprises the steps of forming an inoculum including a preselected fungus; forming a mixture of a substrate of discrete particles and a nutrient material that is capable of being digested by the fungi; adding the inoculum to the mixture; and allowing the fungus to digest the nutrient material in the mixture over a period of time sufficient to grow hyphae and to allow the hyphae to form a network of interconnected mycelia cells through and around the discrete particles thereby bonding the discrete particles together to form a self-supporting composite material.

Where at least one of the inoculum and the mixture includes water, the formed self-supporting composite material is heated to a temperature sufficient to kill the fungus or otherwise dried to remove any residual water to prevent the further growth of hyphae.

The method may be carried out in a batchwise manner by placing the mixture and inoculum in a form so that the finished composite material takes on the shape of the form. Alternatively, the method may be performed in a continuous manner to form an endless length of composite material.

The method employs a step for growing filamentous fungi from any of the divisions of phylum Fungi. The examples that are disclosed focus on composites created from basidiomycetes, e.g., the “mushroom fungi” and most ecto-mycorrhizal fungi. But the same processes will work with any fungi that utilizes filamentous body structure. For example, both the lower fungi, saphrophytic oomycetes, the higher fungi, divided into zygomycetes and endo-mycorrhizal fungi as well as the ascomycetes and deutoeromycetes are all examples of fungi that possess a filamentous stage in their life-cycle. This filamentous stage is what allows the fungi to extend through its environment creating cellular tissue that can be used to add structural strength to a loose conglomeration of particles, fibers, or elements.

The invention also provides materials and composite materials, whose final shape is influenced by the enclosure, or series of enclosures, that the growth occurs within and/or around.

In accordance with the invention, the discrete particles may be of any type suited to the use for which the material is intended. For example, the particles may be selected from the group consisting of at least one of vermiculite and perlite where the composite material is to be used as a fire-resistant wall. Also, the particles may be selected from the group consisting of at least one of straw, hay, hemp, wool, cotton, rice hulls and recycled sawdust where composite material is to be used for insulation and strength is not a necessary criteria. The particles may also include synthetic insulating particles, such as, foam based products and polymers.

These and other objects and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings wherein:

FIG. 1 illustrates a simplified flow chart of the method employed for making a fungi bonded material in accordance with the invention;

FIG. 2 illustrates a schematic life cycle of Pleurotus ostreatus;

FIG. 3 illustrates an inoculated substrate before growth in an enclosure in accordance with the invention;

FIG. 4 illustrates an inoculated substrate after three days of growth in accordance with the invention;

FIG. 5 illustrates an inoculated substrate nearing the end of the growth in accordance with the invention;

FIG. 6 illustrates a final composite of one embodiment composed of nutrient particles and a bulking particle in accordance with the invention;

FIG. 7 illustrates a composite with internal features in accordance with the invention;

FIG. 8 illustrates an enclosure containing a filter disk, temperature sensor, humidity sensor and heat exchange mechanism in accordance with the invention; and

FIG. 9 illustrates an enclosure lid with a rectangular extrusion in accordance with the invention.

Referring to FIG. 1, the method of making a self-supporting structural material is comprised of the following steps.

-   -   0. Obtain substrate constituents, i.e. inoculum in either a         sexual or asexual state, a bulking particle or a variety of         bulking particles, a nutrient source or a variety of nutrient         sources, a fibrous material or a variety of fibrous materials         and water.     -   1. combining the substrate constituents into a growth media or         slurry by mixing the substrate materials together in volumetric         ratios to obtain a solid media while the inoculum is applied         during or following the mixing process.     -   2. applying the growth media to an enclosure or series of         enclosures representing the final or close to final geometry.         The media is placed in an enclosure with a volume that denotes         the composite's final form including internal and external         features. The enclosure may contain other geometries embedded in         the slurry to obtain a desired form.     -   3. growing the mycelia, i.e. filamentous hyphae, through the         substrate. The enclosure is placed in an environmentally         controlled incubation chamber as mycelia grows bonding the         bulking particles and consuming the allotted nutrient(s).     -   3a. repeating steps 1-3 for applications in which materials are         layered or embedded until the final composite media is produced.     -   4. removing the composite and rendering the composite         biologically inert. The living composite, i.e. the particles         bonded by the mycelia, is extracted from the enclosure and the         organism is killed and the composite dehydrated.     -   5. completing the composite. The composite is post-processed to         obtain the desired geometry and surface finish and laminated or         coated.

The inoculum is produced using any one of the many methods known for the cultivation and production of fungi including, but not limited to, liquid suspended fragmented mycelia, liquid suspended spores and mycelia growing on solid or liquid nutrient.

Inoculum is combined with the engineered substrate, which may be comprised of nutritional and non-nutritional particles, fibers, or other elements. This mixture of inoculum and substrate is then placed in an enclosure.

In step 3, hyphae are grown through the substrate, with the net shape of the substrate bounded by the physical dimensions of the enclosure. This enclosure can take on any range of shapes including rectangles, boxes, spheres, and any other combinations of surfaces that produce a volume. Growth can occur both inside the enclosure and outside of the enclosure depending on desired end shape. Similarly, multiple enclosures can be combined and nested to produce voids in the final substrate.

Other elements embedded with the slurry may also become integrated into the final composite through the growth of the hyphae.

The hyphae digest the nutrients and form a network of interconnected mycelia cells growing through and around the nutrients and through and around the non-nutrient particles, fibers, or elements. This growth provides structure to the once loose particles, fibers, elements, and nutrients, effectively bonding them in place while bonding the hyphae to each other as well.

In step 4, the substrate, now held tightly together by the mycelia network, is separated from the enclosure, and any internal enclosures or elements are separated away, as desired.

The above method may be performed with a filamentous fungus selected from the group consisting of ascomycetes, basidiomycetes, deuteromycetes, oomycetes, and zygomycetes. The method is preferably performed with fungi selected from the class: Holobasidiomycete.

The method is more preferably performed with a fungus selected from the group consisting of:

-   -   pleurotus ostreatus     -   Agrocybe brasiliensis     -   Flammulina velutipes     -   Hypholoma capnoides     -   Hypholoma sublaterium     -   Morchella angusticeps     -   Macrolepiota procera     -   Coprinus comatus     -   Agaricus arvensis     -   Ganoderma tsugae     -   Inonotus obliquus

The method allows for the production of materials that may, in various embodiments, be characterized as structural, acoustical, insulating, shock absorbing, fire protecting, biodegrading, flexible, rigid, water absorbing, and water resisting and which may have other properties in varying degrees based on the selection of fungi and the nutrients. By varying the nutrient size, shape, and type, the bonded bulking particle, object, or fiber, size, shape, and type, the environmental conditions, and the fungi strain, a diverse range of material types, characteristics and appearances can be produced using the method described above.

The present invention uses the vegetative growth cycle of filamentous fungi for the production of materials comprised entirely, or partially of the cellular body of said fungi collectively known as mycelia.

FIG. 2 shows a schematic representation of the life cycle of Pleareotus Ostreatus, filamentous fungi. The area of interest for this invention is the vegetative state of a fungi's life cycle where a fungi is actively growing through the extension of its tube like hyphae.

In this Description, the following definitions are specifically used: Spore: The haploid, asexual bud or sexual reproducing unit, or “seed”, of a fungus.

Hyphae: The thread-like, cellular tube of filamentous fungi which emerge and grow from the germination of a fungal spore.

Mycelium: The collection of hyphae tubes originating from a single spore and branching out into the environment.

Inoculum: Any carrier, solid, aerated, or liquid, of an organism, which can be used to transfer said organism to another media, medium, or substrate.

Nutrient: Any complex carbohydrate, polysaccharide chain, or fatty group, that a filamentous fungi can utilize as an energy source for growth.

Fungi Culturing for Material Production

Methodology

Procedures for culturing filamentous fungi for material production.

All methods disclosed for the production of grown materials require an inoculation stage wherein an inoculum is used to transport an organism into a engineered substrate. The inoculum, carrying a desired fungi strain, is produced in sufficient quantities to inoculate the volume of the engineered substrates; inoculation volume may range from as low as 1% of the substrates total volume to as high as 80% of the substrates volume. Inoculum may take the form of a liquid carrier, solid carrier, or any other known method for transporting an organism from one growth supporting environment to another.

Generally, the inoculum is comprised of water, carbohydrates, sugars, vitamins, other nutrients and the fungi. Depending on temperature, initial tissue amounts, humidity, inoculum constituent concentrations, and growth periods, culturing methodology could vary widely.

EXAMPLE 1—PRODUCTION OF A GROWN MATERIAL USING AN ENCLOSURE

The bonding of the grown material is derived primarily from the fungi cellular body, mycelia, that forms throughout and around the engineered substrate. The overall properties of the material are set by the behavior of multiple particles, fibers, and other elements, acting in concert to impart material characteristics, much like in the creation of other composites. The enclosure or enclosures sets the final shape that of the material.

Referring to FIG. 2, the life cycle of Pleurotus ostreatus proceeds from zygote formation (1) to ascus (2) with multiplicity of ascopores (3) and then to hypha formation (4) with the hyphae being collectively called mycelium (5).

FIG. 3 shows a side view of one embodiment i.e. an insulating composite, just after inoculation has taken place.

In this embodiment, a group of nutritional particles 1 and a group of insulating particles 2 were placed in an enclosure 5 to form an engineered substrate 6 therein. The enclosure 5 has an open top and determines the final net shape of the grown composite. Thereafter, an inoculum 3 was applied directly to the surface of the engineered substrate 6.

Shortly after the inoculum 3 was applied to the surface, hyphae 4 were visible extending away from the inoculum 3 and into and around the nutritional particles 1 and insulating particles 2.

FIG. 4 shows a side view of the same embodiment described above, i.e. an insulating composite, approximately 3 days after the inoculum 3 was applied to the surface of the engineered substrate 6. Hyphae 3 have now penetrated into the engineered substrate 6 and are beginning to bond insulating particles 2 and nutritional particles 1 into a coherent whole.

FIG. 5 shows a side view of the same embodiment of FIGS. 3 and 4, i.e. an insulating composite, approximately 7 days after the inoculum 3 was applied to the surface of the engineered substrate 6. Hyphae 3, collectively referred to as mycelia 7, have now fully colonized the top half of engineered substrate 6, bonding insulating particles 2 and nutritional particles 1 into a coherent whole.

FIG. 6 shows a side view of the same embodiments of FIGS. 3, 4 and 5, i.e. an insulating composite, after the engineered substrate 6 has been fully colonized and bonded by mycelia 7. A cutaway view shows a detail of a single insulating particle bound by a number of hyphae 4. Also shown within this embodiment are fibers 9 bound within mycelia 8.

EXAMPLE 2—STATIC EMBODIMENT—COMPOSITE WITH UNIQUE SHAPE AND INTERNAL FEATURES

FIG. 7 shows a perspective view of one embodiment of a mycelia bonded composite composed of nutritional particles, bulking particles, fibers, and insulating particles. This embodiment includes a void near the center that is preserved in the final composite. The preferred use for this composite is a packing material wherein the device to be packed is completely, or partially, placed within a void or series of voids formed by the grown composite.

In this embodiment of a mycelia bonded composite, the following growth conditions and materials were used: The engineered substrate was composed of the following constituents in the following percentages by dry volume:

-   -   1. Rice Hulls, purchased from Rice World in Arkansas, 50% of the         substrate.     -   2. Horticultural Perlite, purchased from World Mineral of Santa         Barbra Calif., 15% of the substrate.     -   3. DGS, dried distillers grains, sourced from Troy Grain Traders         of Troy N.Y., 10% of the substrate.     -   4. Ground cellulose, composed of recycled paper ground into an         average sheet size of 1 mm×1 mm, 10% of the substrate.     -   5. Coco coir, sourced from Mycosupply, 10% of the substrate.     -   6. Inoculum composed of rye grain and inoculated with Plearotus         Ostreatus, 3% of the substrate.     -   7. Birch sawdust, fine ground, 2% of the substrate by volume.     -   8. Tap water, from the Troy Municipal Water supply, was added         until the mixture reached field capacity, an additional 30% of         the total dry substrate volume was added in the form of water.

These materials were combined together in a dry mix process using a rotary mixer to fully incorporate the particles, nutrients, and fibers. Water was added in the final mixing stage. Total mixing time was 5 minutes.

After mixing, the inoculated substrate was transferred to a series of rectangular enclosures. Lids were placed on these enclosures containing block shaped extrusions. These extrusions produced corresponding net shape voids in the loose fill particles as indicated in FIG. 7.

The enclosures were incubated for 14 days at 100% RH humidity and at a temperature of 75° Fahrenheit. The enclosures serve as individual microclimates for each growing substrate set. By controlling the rate of gas exchange, humidity can be varied between RH 100%, inside an enclosure, and the exterior humidity, typically RH 30-50%. Each rectangular enclosure fully contained the substrate and inoculum preventing gaseous exchange. Opening the enclosures lids after 5 and 10 days allowed gaseous exchange. In some cases, lids included filter disks allowing continuous gas exchange.

After 14 days of growth, the enclosures were removed from the incubator. The loose fill particles and fibers have now been bonded into a cohesive whole by the fungi's mycelium producing a rectangular object with a net shape closely matching that of the growth enclosure. This net shape includes a corresponding void where the enclosure lid's extrusion intersected the substrate. This panel was then removed from the enclosure by removing the lid, inverting the growth container, and pressing gently on the bottom.

The mycelia bonded panel was then transferred to a drying rack within a convection oven. Air was circulated around the panel until fully dry, about 4 hours. Air temperature was held at 130° Fahrenheit.

After drying, the now completed composite is suitable for direct application as a packaging material or can be post processed to include other features or additions including water resistant skins, stiff exterior panel faces, and paper facings.

Within the above embodiment, the ratios and percentages of bulking particles, insulating particles, fibers, nutrients, inoculum, and water can be varied to produce composites with a range of properties. The materials expanded perlite compositions can vary from 5%-95% of the composite by volume. Other particles, including exfoliated vermiculite, diatomic earth, and ground plastics, can be combined with the perlite or substituted entirely. Particle sizes, from horticultural grade perlite to filter grade perlite are all suitable for composite composition and many different composite types can be created by varying the ratio of perlite particle size or vermiculite or diatomic earth particle size.

Rice hulls can compose anywhere from 5-95% of the composite material by volume. Fibers can compose from 1-90% of the material by volume. DGS can compose between 2-30% of the substrate by volume. The inoculum, when in the form of grain, can compose between 1-30% of the substrate by volume. Ground cellulose, sourced from waste paper, can compose from 1-30% of the substrate by volume.

Other embodiments may use an entirely different set of particles from either agricultural or industrial sources in ratios sufficient to support the growing of filamentous fungi through their mass.

Though not detailed in this preferred embodiment, the engineered substrate can also contain internal elements including: rods, cubes, panels, lattices, and other elements with a dimension minima 5 times larger than the mean diameter of the largest average particle size.

In this embodiment, the fungi strain Pleurotus ostreatus was grown through the substrate to produce a bonded composite. Many other filamentous fungi's could be used to produce a similar bonding result with differing final composite strength, flexibility, and water sorption characteristics.

In this embodiment, the substrate was inoculated using Pleurotus ostreatus growing on rye grain. Other methods of inoculation, including liquid spore inoculation, and liquid tissue inoculation, could be used with a similar result.

Incubation of the composite was performed at 100% RH humidity at 75° Fahrenheit. Successful incubation can be performed at temperatures as low as 35° Fahrenheit and as high as 130° Fahrenheit. RH humidity can also be varied to as low as 40%.

In this embodiment, only one void of a square shape was shown, but such a product could include multiple voids in many shapes to match the dimensions of product enclosed within the voids.

EXAMPLE 3—GROWTH ENCLOSURE—FIG. 8

Referring to FIG. 8, a square growth enclosure is provided with a lid to produce composite panels with an equivalent net shape. The panels are produced using a process similar to that outlined in example 1 and 2.

The shape of the enclosure used for composite production determines the eventual shape of the final product. In FIG. 9, the orthogonally oriented sides, left 13 and front 14, form a corner with bottom 15, this corner feature, as other enclosure induced net shapes, will be replicated in the grown composite.

Beyond producing the equivalent net shape of a grown composite, the enclosure provides a number of other unique functions. These include: gas exchange regulation, humidity regulation, humidity sensing, temperature sensing, and heat removal.

FIG. 8 shows a filter disk 16 that is sized and calibrated to the shape and volume of the growth enclosure. This filter disk 16 allows the growing organism to respirate, releasing CO2 and up taking O2, without the exchange of other particles in the room. This disk 16 also allows some moisture to travel from substrate to the incubation environment, and vice versa. Typically, a filter disk system would be passive, designed to allow the correct respiration rate for the specific substrate, fungi type, and volume of material, growing within the enclosure. In some cases, where active control over an individual incubation environment is desired, a filter disk could have an aperture that is dynamically altered to slow or increase the rate of gaseous exchange with the incubation environment.

FIG. 8 also shows a temperature control mechanism 17, comprised of a network of tubing 20, that can be used to remove or add heat to the enclosure. The growth of fungi relies on a decomposition reaction. Hence, in most cases where additional heat control is required beyond that provided by the convective interactions occurring along the exterior enclosures surface, it will be in the form of heat removal. A network of tubes or other heat exchange mechanism allows both more precise control over the amount of heat removed or added to the enclosure and allows an overall greater amount of heat to be removed or added to the growth enclosure in a shorter period of time.

FIG. 8 also shows a temperature sensor 18 and humidity sensor 19. These sensors measure the internal temperature and humidity of the enclosure, respectively. This data can then be transmitted to a collection unit for analysis, or be used to alter the environment of the enclosure through the dynamic re-sizing of a filter disk aperture or through changes in temperature made possible through the temperature control mechanism.

FIG. 9 shows a growth enclosure lid with a protrusion 21. When this lid is used in conjunction with a matching bottom growth enclosure, the protrusion 21 will effect the overall net shape of the enclosed volume producing features in the grown composite that relate directly to those in the lid, such as protrusion 21. Such a process was used to produce the composite shown in FIG. 8 where the lid, shown in FIG. 10 has a protrusion 20, that modifies the enclosed net volume of its growth enclosure producing a unique feature 12 within composite 10 (see FIG. 8).

EXAMPLE 4—PRODUCTION USING FEATURE MOLDING

Production of a grown material using an enclosure and feature molding, i.e. a tool or other object to create a feature relief within a growing shape of substrate.

Plearotus Ostreatus, or any other filamentous fungi, is cultured from an existing tissue line to produce a suitable mass of inoculum. The inoculum may take the form of a solid carrier, liquid carrier, or any other variation thereof.

To produce a grown material using a molding based manufacturing technique, the following steps are taken:

-   -   1. Creation of an engineered substrate comprised of nutritional         particles, fibers, non-nutritional particles, and other         elements.     -   2. Disposition of the substrate within an enclosure or series of         enclosures with voids designed to produce the desired final         shape.     -   3. Inoculation of the substrate within the enclosure with the         inoculum containing the desired fungi strain.     -   4. Growing the desired fungi strain through the engineered         substrate within the enclosure or enclosures.     -   5. Forcefully molding additional features into the engineered         substrate by compressing a tooling piece with extruded features         into one of the faces of the engineered substrate.     -   6. Allowing the living substrate to recover.     -   7. Removal of the substrate from the enclosure or enclosures.         Alternatively, the method may use the following steps:     -   1. Creation of an engineered substrate comprised of nutritional         particles, fibers, non-nutritional particles, and other         elements.     -   2. Inoculation of the engineered substrate with the inoculum         containing the desired fungi strain.     -   3. Disposition of the substrate within an enclosure or series of         enclosures with voids designed to produce the desired final         shape.     -   4. Growing the desired fungi strain through the engineered         substrate within the enclosure or enclosures.     -   5. Forcefully molding additional features into the engineered         substrate by compressing a tooling piece with extruded features         into one of the faces of the engineered substrate.     -   6. Allowing the living substrate to recover.     -   7. Removal of the bonded engineered substrate from the enclosure         or enclosures.         Alternative Substrates

Organic materials can be implemented in the mycelium insulation growth process as insulating particles and the complex carbohydrate. Currently, insulating particles such as vermiculite or perlite are bound within the mycelium cellular matrix, but other natural materials have identical if not superior insulating characteristics, such as:

Straw/Hay/Hemp: material is either woven into a mesh or laid within the slurry mixture, as the mycelium grows the material is bound forming an insulation panel with variable layer thickness.

Wool/Cotton: the material is woven into a fibrous mesh or fragmented forming small insulating particles that a bound within the mycelium as it grows. The slurry can be applied directly to the mesh or the particles can be mixed in during the slurry production. The particle material can be grown or obtained from reused clothing that contains a large percentage of wool/cotton.

Recycled sawdust can replace the current polysaccharide, which is a form of starch or grain, as the mycelium food source during the early growth stages. Sawdust can be collected from businesses that create the dust as a byproduct or from natural collections methods.

The insulating particles can consist of new, recycled, or reused synthetic particles, which are already known to have insulating properties or leave a detrimental environmental footprint. Materials currently considered include:

Foam Based Products: recycled and reused foam insulators or foam garbage, such as Styrofoam cup and packaging, which are broken into small particles of varying or congruent sizes and applied to the slurry. The foam material can be obtained from existing disposed of material or newly fabricated products.

Rubber/Polymers: these materials can be found in a myriad of products, which can be reused after the desired life-cycle of the aforementioned product is reached. The material can be applied into the slurry as a ground particle or implemented as a structural member within the growth in various configurations. 

What is claimed is:
 1. A method of making a self-supporting composite material comprising the steps of creating an engineered substrate comprised of a nutrient source and at least one of discrete particles and fibers; disposing the substrate within an enclosure in an amount to fill said enclosure; inoculating the substrate within the enclosure with an inoculum containing a desired fungi strain; growing the desired fungi strain through the engineered substrate within the enclosure for a time sufficient for said fungal strain to digest said nutrient source, to grow hyphae and to allow said hyphae to form a network of interconnected mycelia cells through and around said at least one of discrete particles and fibers thereby bonding said at least one of discrete particles and fibers together to form a cohesive whole with a shape matching the internal shape of said enclosure; compressing a tooling piece with at least one protrusion into at least one face of the engineered substrate during growth of said fungi strain to forcefully mold a corresponding feature to said protrusion into the engineered substrate and resultant cohesive whole; and thereafter removing the cohesive whole from said enclosure and drying the cohesive whole. 